A new type of reduced graphene oxide-CuInS2(rGO-CuInS2) composite was successfully synthesized via solvothermal method. The structure of composite was characterized by X-ray diffraction (XRD), Raman, UV-Vis (UV-Vis), photoluminescence (PL) spectra, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy(HRTEM). The results show that CuInS2 quantum dots, with a size of 3-5 nm, disperses uniformly on the surface of graphene. In addition, the growth mechanism of the composite was also investigated. And the rGO-CuInS2 composites with different rGO/CuInS2 mass ratio were applied in hybrid photovoltaic device. Compared with the power conversion efficiency (θ) of the device based on reduced graphene oxide (rGO), the device based on rGO-CuInS2 composites exhibit higher performance with the highest θof 1.10% when the composite mass ratio is 0.5:1.